Atari published unreal tournament. Thats the single most time I've spent on a game, including MMORPhegers. Don't have a spare box for LAN battles now though.
Also, you don't need a disk in the drive to play UT, it will also install on 3 computers in LAN no problem. Just recently I bought the game again because I had scratched the disks to death, the serial that was supposed to be in the box was missing. I called the number in the manual and they gave me a new one. No fuss, no international calls.